Posted
by
CmdrTacoon Thursday May 28, 2009 @08:44AM
from the this-sounds-all-wet dept.

Matt_dk writes "NASA scientists modeled freezing conditions on Mars to test whether liquid water could have been present to form the surface features of the Martian landscape.
Evidence suggests flowing water formed the rivers and gullies on the Mars surface, even though surface temperatures were below freezing. Dissolved minerals in liquid water may be the reason."

The current theory is that a lot if not most of the water on earth came from water comets bombarding it after it had solidifed and cooled enough so that the water didn't just boil away out of the atmosphere.

Where is the salt that life is pissing into the water coming from? Pretty sure it would come from the salty water as well. This would mean the water would not get saltier as more life pisses into the water. Not saying the rest of your statement is wrong, but the life making water saltier seems to be circular logic.

However, someone else made the point that the current theory is that Earth received much of its water from "magical" water comets. I seem to recall that many of them are made of ice, now what does

Not saying you're wrong, but where does the water in the comets come from? If it can form in comets, isn't it also possible that water is a common compound which can form anywhere conditions allow (i.e. the presence of hydrogen and oxygen and a catalyst to fuse them)?

The comet theory is interesting, but it also begs the question.

As for the salts, the additional minerals would come from the metabolic processes of the life. The life grows by absorbing sunlight (or something) and ingesting the riverbed mineral

My understanding is that water is a relatively common compound, but the problem is that oxygen and hydrogen (esp. hydrogen) are light and therefore less likely to survive the creation of a rocky inner planet. A planet is formed from the outcasts of matter from a forming star. The heavier elements converge toward the center and the lighter ones get pushed out. Any water that is not blown away from the rocky planet by solar winds and such are boiled away by the hot, forming planet. These less-dense materials

Still valid, but this is not the question. They are trying to determine wether big bodies of water existed on Mars. About Mars having huge quantities of water ice, we know it from several years, we even have pictures [esa.int] of it and even a map [blogspot.com] of Mars' aquifers.

It's been suggested recently that the perchlorates invalidated the micro-oven experiments, Apparently when heated they release large amounts of oxygen that would incerate any organics. Since I only have a vauge idea of what a perchlorate is, I have no idea if that's a valid criticisim. But given the possibility of ground water I think the methane hots spots [google.com.au] are worth a closer look.

Is it possible that mars was warmer at a time? Either with a high level of CO2 or some other greenhouse gas that would have warmed the surface enough for running water? Maybe a little more dramatic but maybe even a slightly closer orbit?

Is it possible that mars was warmer at a time? Either with a high level of CO2 or some other greenhouse gas that would have warmed the surface enough for running water?

Yes, that's a good summary of the current scientific thinking. The Viking orbital images show a lot of the surface is sculpted by water-carved features, and the belief is that Mars originally has a much thicker carbon dioxide atmosphere, which provided a significant amount of greenhouse warming (*). With the loss of Mars' magnetic field, this thick atmosphere was slowly eroded away by the solar wind to the very thin atmosphere we see today.

Maybe a little more dramatic but maybe even a slightly closer orbit?

No, that's quite unlikely. Planets are hard to move.

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*Footnote: The media likes to pretend that there is some controversy about the fact that carbon dioxide produces greenhouse effect warming (because controversy sells newspapers), but in the science community studying planetary atmosphere, there is no controversy whatsoever. It is just physics.

If you search hard enough, you can find somebody who disagrees, and quote them, and say, "look, not all scientists agree!" And since this is/. I'm sure somebody's about to do that: the miracle of the internet is that these fringe thinkers have just as loud a voice as people who have actually stufied the subject. But nevertheless, the greenhouse effect is just physics. And relatively simple physics.

Not so fast.:-) We have to look at the orbital decay to figure that one out. If Mars has to much velocity for its orbit, it'll work farther out. If it has too little velocity, it'll fall in.

Well, sort of. It won't "work its way out": if a planet has too much velocity for a circular orbit it will be in an elliptical orbit (it won't "work its way" into an elliptical orbit-- it will be in an elliptical orbit). However, if you work out how much energy that takes to move the planet, the number is, uh, extremely large. Planets are hard to move.

Combine that with tidal forces of the planets and the asteroid belt, and you might have a measurable affect.

Indeed, you "might." Turns out, however, that the perturbations do add up, but they don't add up enough to a large enough effect to significantly affect t

My frost-bit annuals, planted well after the last-frost date for this location, beg to differ...

Yeah, this is exactly the kind of irrelevent arguments you tend to hear. To be fair, the idiotic media hype makes it seem as if this really is the argument for global warming: one warmer-than-average summer, and the headlines read "Global warming is here," and one worse-than-average hurricane season and headlines say "Global warming! Hurricanes are getting worse!"

Global warming is a long-term average rise of temperature over time scales of decades. One warm winter, even a handful of warm winters, has no

I think the problem is that many people think the controversy is whether or not global warming is happening. The answer is that it is happening, the global average temperature is climbing. This is based on hard evidence obtained by measuring. Arguing that it isn't is like arguing that the world is flat. The real question and controversy is whether or not our past and present actions are having a measurable effect. All scientists can do is run small controlled experiments, and eventually come up with a theor

I think the problem is that many people think the controversy is whether or not global warming is happening. The answer is that it is happening, the global average temperature is climbing. This is based on hard evidence obtained by measuring. Arguing that it isn't is like arguing that the world is flat. The real question and controversy is whether or not our past and present actions are having a measurable effect.

Yes, that's the problem-- if you listen to the media, you would indeed think that this is a "controversy."

It is not a controversy. It is a settled question. There are vast amounts of data, extremely detailed computer models, vertical temperature profiles, satellite measurements. The "controversy" does not exist. The controversy is entirely manufactured by people pushing a "there is no global warming so we don't have to do anything" agenda.

The atmospheric composition of Mars is predominantly CO2 (95%). If you take some eco-nut stance, the warming is linear, if you take a better-modeled stance you'll find it is less than that. (Diminishes logarithmically)

The real question is one of geology. Was Mars' inner core capable of producing a protective magnetic should like the Earth's? Remember Mars is smaller and will therefore cool faster. Our core, as the theory goes is made by counter-rotating spheres of liquid iron. With this, comes a thick, rich

That's a good point about the core of the planet, I remember reading that only the Earth has the protective magnetic field. Is it possible, and this will draw on my real lack of geology, but would a shift in orbit, say a collision that formed the "moons" of Mars pushed it out, and had enough either change in temperature of maybe a collision itself was disruptive enough to stop it from working?

OPINION: There is enough evidence to suggest that Mars could have been roughly equivalent to tropical - humid and warm. Weather or not its breathable is a whole other story with all that supposed methane...

The pressure and temperature matter more than whether you can breathe the atmosphere without a mask. But maybe I'm just biased towards a rapid terraforming model:)

The only problem I can see with all your comments is that you are assuming this took place a long time ago. We know that Mars can reach the mid 20s C and we also know that there are massive periodic dust storms. Don't you think the storms would have eroded away the water gullies, or at least filled them with dust by now ? So I would say the formations are a lot more recent than "in the ancient past when Mars had a bigger atmosphere".

That's a very good question. But the problem is one of sublimation. That is from solid state to gas. It happens in cold dry air. Snowcap-free Mt Kilimanjaro in Al Gore's "Incon. Truth" didn't melt from global warming. It sublimated because farming on the windward side made the air passing over the mountain drier.

The only way to keep the liquid water around is to have a denser, wetter atmosphere.

The problem with storms filling in gullies is that the dust particles are very fine, and have to be since there's not a lot of gas to move them. Without moisture, it is hard to bond to other particles (static charge being the leading cause) so its hard to have some drift that won't be blown away at the next dust storm.

That being said, there is evidence of water percolating. This won't be able to make large new gullies, but it will help maintain the ones that are there. And in fact, we have no idea of the gullies that exist that are filled in by dust. I can only conclude that the gullies we see are stable features left over from a time long ago. The "last of the line" so to say.

...we also know that there are massive periodic dust storms.
Don't you think the storms would have eroded away the water gullies, or at least filled them with dust by now ? So I would say the formations are a lot more recent than "in the ancient past when Mars had a bigger atmosphere".

The cross-section weighted average particle size of the dust particles is about 5 microns. Think of the particles as being ten times finer than the particles that make up talcum powder. It's more like cigarette smoke than it's like sand; it's not very abrasive, and doesn't do much in the way of erosion.

Sandstorms, like we have on Earth, do much more erosion.

However, yes, burial and deflation of features is a well-known effect on Mars. In some places the ancient surface is exposed, but in other places i

We've so many things to learn from our red neighbor. I hate to put my tin foil hat on this early in the day, but I oft wonder how much data has been retrieved/analyzed/hypothesized upon that we (mouth breathers at-large) have not been made aware of. There are some tantalizing possibilities with Mars, both to learn of our past and to help forge our future. Like Buzz Aldrin, I think whomever the first Mars pioneers wind up being, they should not plan on returning...

Wow, another speculative article from someone one what COULD have been. I wish one of these days NASA would give me more than models, simulations, possibilities, and probes that are SUPPOSED to reveal actual conclusive evidence but which never do.

"We found that the salts in water solutions can reduce the melting point of water, which may help explain how liquid water existed in a frozen Martian environment" -- Alberto Fairen, a space scientist at NASA Ames Research Center, Moffett Field, Calif. and the lead author of the study.

Scientists concluded that salty liquid water on Mars may explain the stability of fluids against freezing on the Martian surface at temperatures below 0C

In college( 40 years ago) we poured the salt shakers into the ice water and then stuck the glass on a pat of butter to bond it to the trays. I don't find the speculation very interesting or new, either, and I will add that since they have no complete knowledge, and a way to verify, the planet could have been covered in fudge and cellophane.More scientifically, I could say that there are so many dimensions in the NULL space of that matrix that selecting one of infinite possible vector solutions is just silly

Actually, the pivotal factor is the great flood. The truth is we (human beings) were created by God within a 7 day period etc etc... BUT the original home for us was MARS. Hence the drastically different life spans, physiological discrepancies (giants and other deviations)and the environment.

Having completed this beta phase and learned some valuable lessons, God took the opportunity to launch His RC on Earth and implement the necessary changes to continue development (see changelog commonly known as bible